- Ontario County, New York, United States1
- Orange County, New York, United States1
- Orissa (India)1
- Orleans County, New York, United States1
- Oromocto, Canada1
- Oswego County, New York, United States1
- Otsego County, New York, United States1
- Outlook, Canada1
- Oxbow, Canada1
- Papineauville, Canada1
- Parksville, Canada1
- Patna district, Bihar, India1
- Pemberton, Canada1
- Phek, Nagaland, India1
- Philadelphia, Pennsylvania, United States1
- Phoenix, Arizona, United States1
- Pickering, Canada1
- Pilot Butte, Canada1
- Pittsburgh, Pennsylvania, United States1
- Pondicherry (India : Union Territory)1